55 lines
1.0 KiB
C++
55 lines
1.0 KiB
C++
#include "samplingthread.h"
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#include "signaldata.h"
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#include <qwt_math.h>
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#include <math.h>
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#if QT_VERSION < 0x040600
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#define qFastSin(x) ::sin(x)
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#endif
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SamplingThread::SamplingThread( QObject *parent ):
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QwtSamplingThread( parent ),
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d_frequency( 5.0 ),
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d_amplitude( 20.0 )
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{
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}
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void SamplingThread::setFrequency( double frequency )
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{
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d_frequency = frequency;
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}
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double SamplingThread::frequency() const
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{
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return d_frequency;
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}
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void SamplingThread::setAmplitude( double amplitude )
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{
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d_amplitude = amplitude;
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}
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double SamplingThread::amplitude() const
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{
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return d_amplitude;
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}
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void SamplingThread::sample( double elapsed )
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{
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if ( d_frequency > 0.0 )
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{
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const QPointF s( elapsed, value( elapsed ) );
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SignalData::instance().append( s );
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}
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}
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double SamplingThread::value( double timeStamp ) const
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{
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const double period = 1.0 / d_frequency;
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const double x = ::fmod( timeStamp, period );
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const double v = d_amplitude * qFastSin( x / period * 2 * M_PI );
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return v;
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}
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